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        <p>Library Version 12.1.6.2</p>
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          <th colspan="3" align="center">DB_ENV-&gt;rep_set_clockskew()</th>
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                Replication Methods
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            <h2 class="title" style="clear: both"><a id="repclockskew"></a>DB_ENV-&gt;rep_set_clockskew()</h2>
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      <pre class="programlisting">#include &lt;db.h&gt;

int
DB_ENV-&gt;rep_set_clockskew(DB_ENV *env,
    u_int32_t fast_clock, u_int32_t slow_clock);  </pre>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_clockskew()</code> method sets the
         clock skew ratio among replication group members based on the fastest
         and slowest clock measurements among the group for use with master
         leases.
         Calling this method is optional; the default values for clock skew
         assume no skew.  The application must also configure leases via the 
         <a class="xref" href="repconfig.html" title="DB_ENV-&gt;rep_set_config()">DB_ENV-&gt;rep_set_config()</a> 
         method and set the master lease timeout via the 
         <a class="xref" href="repset_timeout.html" title="DB_ENV-&gt;rep_set_timeout()">DB_ENV-&gt;rep_set_timeout()</a> 
         method. Base API applications must also set the
         number of sites in the replication group via the 
         <a class="xref" href="repnsites.html" title="DB_ENV-&gt;rep_set_nsites()">DB_ENV-&gt;rep_set_nsites()</a> 
         method.  These methods may be called in any order.  For a description
         of the clock skew values, see 
         <a href="../../programmer_reference/rep_clock_skew.html" class="olink">Clock skew</a>
         in the <em class="citetitle">Berkeley DB Programmer's Reference Guide</em>.  For a description of
         master leases, see 
         <a href="../../programmer_reference/rep_lease.html" class="olink">Master leases</a> in the
         <em class="citetitle">Berkeley DB Programmer's Reference Guide</em>.
    </p>
      <p>
         These arguments can be used to express either raw measurements of a
         clock timing experiment or a percentage across machines.  For example, if
         a group of sites has a 2% variance, then <span class="bold"><strong>fast_clock</strong></span> should be set to 102, and
         <span class="bold"><strong>slow_clock</strong></span> should be set to 100.  Or,
         for a 0.03% difference, you can use 10003 and 10000 respectively.
    </p>
      <p>
         The database environment's replication subsystem may also be
         configured using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The syntax of
         the entry in that file is a single line with the string
         "rep_set_clockskew", one or more whitespace characters, and the
         clockskew specified in two parts: the fast_clock and the
         slow_clock.  For example, "rep_set_clockskew 102 100". Because the
         <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read when the database environment is opened,
         it will silently overrule configuration done before that time.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_clockskew()</code> method configures a database
         environment, not only operations performed using the specified 
         <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_clockskew()</code> method may not be called after the
         <a class="xref" href="repmgrstart.html" title="DB_ENV-&gt;repmgr_start()">DB_ENV-&gt;repmgr_start()</a>  or
         <a class="xref" href="repstart.html" title="DB_ENV-&gt;rep_start()">DB_ENV-&gt;rep_start()</a> 
         methods are called.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_clockskew()</code> <span>
            <span>
                  method returns a non-zero error value on failure and 0 on success.
            </span>
            
        </span>
    </p>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idm140711173815648"></a>Parameters</h3>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idm140711173789696"></a>fast_clock</h4>
              </div>
            </div>
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          <p>
                 The value, relative to the <span class="bold"><strong>slow_clock</strong></span>, 
                 of the fastest clock in the group of sites.
             </p>
        </div>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idm140711173819024"></a>slow_clock</h4>
              </div>
            </div>
          </div>
          <p>
                  The value of the slowest clock in the group of sites.
             </p>
        </div>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idm140711173831648"></a>Errors</h3>
            </div>
          </div>
        </div>
        <p>
             The <code class="methodname">DB_ENV-&gt;rep_set_clockskew()</code> <span>
            <span>
                 method may fail and return one of the following non-zero errors:
            </span>
            
        </span>
        </p>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idm140711173747920"></a>EINVAL</h4>
              </div>
            </div>
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          <p>
                If the method was called after replication is started with a
                call to the 
                <a class="xref" href="repmgrstart.html" title="DB_ENV-&gt;repmgr_start()">DB_ENV-&gt;repmgr_start()</a> or the 
                <a class="xref" href="repstart.html" title="DB_ENV-&gt;rep_start()">DB_ENV-&gt;rep_start()</a> method; or if
                an invalid flag value or parameter was specified.
            </p>
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      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idm140711173750000"></a>Class</h3>
            </div>
          </div>
        </div>
        <p>
                <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  
            </p>
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      <div class="sect2" lang="en" xml:lang="en">
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            <div>
              <h3 class="title"><a id="idm140711173809936"></a>See Also</h3>
            </div>
          </div>
        </div>
        <p>
             <a class="xref" href="rep.html#replist" title="Replication and Related Methods">Replication and Related Methods</a> 
        </p>
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